Often we need an efficient way to generate high
quality pseudo-random numbers in Haskell. We have good generators
themselves (for example, the mersenne-random-pure64 package), however, users
are often tempted to store the generator in a lazy state monad. This
causes performance problems.

This package provides an optimized Rand monad for monadic generation
of random numbers from a state, with close attention to performance. You
may have results an order of magnitude or more better than using
Control.Monad.State to store your generator.